DIV. 1 



THALLOPHYTA 



411 



shaped, brown chromatophores, giving to the algae a yellowish-brown 

 or dark-brown colour. In addition to the pigments of chlorophyll 



FIG. 352. Fucus serratus. To the left the end of an older branch bearing conceptacles. (J nat. size.) 



they contain a special yellow pigment, phycoxanthin (fucoxanthin). A 

 polysaccharid called laminarin arises as a metabolic product from glucose, 

 while in addition mannite is formed. Small vacuoles containing a 

 tannin-like substance called fucosan are generally distributed in the 



